A base station apparatus using an adaptive array antenna calculates a weight of transmission power for each of a plurality of antennas, for transmitted signals, based on signals received by each of the antennas. The base station apparatus transmits signals weighted according to the weight from each of the antennas.
For calculating the weight precisely, it is necessary to measure a received power and a phase rotation of a received signal by each antenna and a power loss and a delay which occur inside the base station apparatus on transmitting signals, and to calculate the weight in consideration of these measures. For this purpose, a variety of calibration technologies have been developed. For example, in Japanese Patent Application Publication No. 2001-053661, a calibration technique for calculating the weight in consideration of the power loss and the delay caused by different characteristics of isolation, loss, etc. between each antenna and between each cable is described.